This paper studied the biomass and productivity of 31-year-old standing forest of Cryptonmeria fortune Hooibrenk.in Liuwan Forestry Station of Guangxi Province.Sample tree biomass was investigated according to different diameter grade.Results showed that the individual biomass of average tree increased with the increase of diameter grade,and biomass with different diameter grade was significantly different;R2value was over 0.983 and reached 0.01 evident level;Tree biomass of different organ ranged in order from strong to week:trunk branch root stump leave dead branchbig rootsmall rootmiddle root;And the total biomass of tree layer reached 239.03 t·hm-2,the trunk biomass was 120.24 t·hm-2,accounting for 50.30% of the whole plant;The annual net productivity was 7.89 t·hm-2·a-1.

[Objective]The aim was to find better culture conditions on multiple shoot multiplication for Melaleuca leucadendron.[Method] The impact of different basic medium,different carbon source and concentration,different hormone combination on multiple shoot multiplication was studied.[Result]The results showed that MS was better basic medium,40 g/L white suger was better carbon source,6-BA 0.8 mg/L+2,4-D0.01 mg/L was better hormone combination.[Conclusion]Multiple shoot multiplication effect related to basic medium.In a certain concentration range,the proliferation times increased with the increase of carbon concentration.Low concentration 2,4-D with low concentration 6-BA was beneficial to multiple shoot multiplication.

[Objective] The study aimed to make sure the wood property of Machilus Paunoi Kanenira.[Method] M.Paunoi was selected from Daguishan Forestry Farm in Guazhou City of Guangxi,the green wood volume were determined by the drainage method and the bark percentage was determined by the volume method and the quality method so as to study the density,bark percentage and heartwood percentage of the green wood of M.Paunoi.[Result] The green wood density of M.Paunoi was reduced with the rising of tree height,with the average value of 0.789 g/cm3.The radial change of the basic density was increased with the increasing tree age.As for the longitudinal change,with the rising of the tree height,the basic density was reduced gradually before the first living branch and was increased gradually,with the average value of 0.454 g/cm3.The moisture content of green wood showed a decreasing trend in the north orientation from the pith to the sapwood and had a trend of first increasing and then decreasing in the south orientation;with the rising of the tree height,the moisture content was increased gradually before the first living branch and had little change after that,with the average value of 73.8%.The bark volume percentage and bark quality percentage were increased with the rising of the tree height,with the average value of 12.2% and 13.2% resp.[Conclusion] This study provided the scientific basis for the protection of main precious tree species in Guangxi and the development of M.Paunoi.

The growth charateristics of Eucalyptus urophylla×E.grandis plantation were studied in northern suburb of Nanning city in Guangxi.The results showed that the stand DBH,height and volume of E.urophylla×E.grandis plantation significantly increased with increasing stand age.The stand volume of E.urophylla×E.grandis plantation of 1.5,2.5,3.5 and 4.5 years old were 2.02,45.59,98.87,134.58 and 152.57 m3/hm2 respectively,showing the characteristic of early rapid growth.With increasing of stand age,the total increment of height,DBH and volume of E.urophylla×E.grandis plantation did not decline,but their annual increment had an obviously decreasing trend.

According to the randomized complete block design,Jatropha curcas seedings were sprayed with different kinds and concentrations of plant growth regulators effects by randomized block design.The paper aimed to find out the appropriate growth regulator program which could best favor the growth of Jatropha curcas seedlings.The result showed that 60 mg/L of NAA or ABT3 could remarkably improve the seedling height,diameter growth,chlorophyll content and soluble sugar content comparing to control.However,CAT activity was slightly lower than the control and they were not significantly different in statistics.

本文利用百度试验法研究了刨花润楠的木材干燥特性，结果表明：刨花润楠属难干木材，干燥速度4级，较慢；截面变形严重，达4级；扭曲明显，为3级；初期开裂和内裂等级分别为1级和2级。参照百度试验缺陷等级以及干燥缺陷对应的干燥条件制定了25-30mm厚刨花润楠木材干燥基准。

[Objective] The aim of the research was to study the effect of plant growth regulator on Castanopsis fissa seedlings,and to seek optimum method for breeding seedlings in production.[Method] Seedlings of Castanopsis fissa were sprayed with different concentrations of ABT3 and NAA.Form indexes such as height, diameter and biomass and physiological indexes such as chlorophyll content of seedling were tested.[Result] Plant growth regulators had obvious accelerative effect on the seedling growth.ABT with 50 mg/L concentration had the most remarkable effect on the growth.The height,stem of seedling,total length of roots,leaf area,chlorophyll content of plants which was sprayed with ABT 50 mg/L reached 27.53%,61.54%,70.91%,64.23% and 21.43% respectively,which were higher than that of the control.[Conclusion] NAA and ABT had obvious effects on accelerating the seedling growth of Castanopsis fissa.And the research provided the basis for usage of the plant growth regulator in the production.

用混合生长素滤纸法,对各物种或变种金花茶进行空中压条比较试验研究.结果表明除武鸣金花茶、龙州金花茶、弄岗金花茶外,所试验物种或变种都可以通过空中压条技术繁殖苗木.